Many types of modular enclosures for commercial and industrial use utilize modular rectangular frames of varying sizes to provide support for wall panels, shelving, work surfaces and the like. The modular frames may be interconnected to provide extended length walls, countertops or shelves. These variations may require special connections along the length of an extended wall or at right angle corners. All of these variations in the modular construction often require special fasteners of varying sizes and types resulting in complex and difficult to assemble modules.